I. Field of the Invention
The present invention relates generally to wireless communication devices and more particularly to a method and apparatus for rejecting over-the-air (OTA) requests for call initialization by a multi-mode wireless communication device.
II. Description of the Related Art
Wireless communications have become commonplace throughout the world. Today's wireless communication devices comprise analog and digital telephones operating at cellular and PCS frequencies, satellite telephones, personal computers equipped with wireless modems, wireless vehicle communication systems, and so on. In the field of wireless telephones, first generation telephones rely on analog transmission protocols to transmit voice communications. More recently, wireless telephones using digital modulation techniques have become prevalent due to the additional benefits inherent with digital technology. For example, digital wireless telephones provide for better voice clarity, fewer dropped calls, and various service options not available on analog wireless telephones.
Wireless connectivity to world-wide computer networks, such as the Internet, is becoming an increasingly desirable attribute for wireless communication devices. An increasing number of wireless applications for mobile telephony and other products using the Internet are becoming more and more common. A next generation of mobile telephones will be able to interact with the Internet with speeds approaching or exceeding speeds available on desktop computers today.
Wireless connectivity to the Internet is just one example of data communications that are, or will soon be, available to wireless communication devices. Presently, data can be transmitted either synchronously or asynchronously. Synchronous data transmission implies that a transmitter and a receiver are synchronized in time with respect to each other, the data being transmitted at specific time intervals. Asynchronous data transmission, on the other hand, uses information transmitted with the data itself to align the receiver to be able to demodulate the received data. An example of synchronous data transmission is what is commonly referred to as "packet data" transmission and is used to transfer data between a computer and the Internet using various transmission protocols, such as TCP/IP. An example of asynchronous data transmission is a dedicated connection between a transmitter and a receiver, such as two computer modems transferring data between them.
In packet data transmission applications, for example a computer connected to the Internet, data is generally sent in bursts, each burst of data usually lasting from a few seconds to minutes or longer. An example of a burst of data over the Internet occurs, for example, when a user accesses a web site. The information contained on the web site is sent to the requesting computer in data packets, which continue, more or less, until all of the requested information has been completely transmitted to the requesting computer. No data is transmitted again until another data request is received from the requesting computer.
In wireless applications, data is also sent in bursts over the air, generally from a base station to a wireless communication device. However, if a general lack of link activity is detected after a relatively short amount of time, the air interface providing a communication channel between the base station and the wireless communication device is "torn down" or de-activated. When a subsequent data request is issued by either the wireless communication device or the base station, a new communication channel must be established.
It is anticipated that in the near future, wireless telephones are expected to be able to provide multiple modes of communication to users. For example, a wireless telephone capable of both voice and data communications is expected shortly.
One problem that may arise as a result of a wireless telephone having multi-mode capability is interruptions from other calls during while the telephone is engaged in certain modes of communication, such as data communications. As stated earlier, when a wireless communication device engages in data communications, relatively lengthy delays between data transfers can often occur. In these cases, a communication channel assigned to the wireless communication may be revoked and re-assigned to another wireless communication device. During the time when no channel is assigned to the first communication device during a data communication, a second communication may be directed to the wireless communication device. The second communication may be, for example, a voice call. When the wireless communication device does not have a communication channel assigned to it, calls of any mode are able to be transmitted to the communication device. For example, a page message may be sent to a communication device requesting a call initialization, or a request to initiate communications with the wireless communication device. The page message and/or the pending voice call will generally disrupt the current data communication.
What is needed is an apparatus and method to disable communications of a first mode to a communication device capable of multi-mode communications. The need for such an apparatus and method is especially useful in applications where a user does not wish to receive calls of the first mode while a communication of a second mode is in progress. The apparatus and method will ideally not require changes to existing infrastructure, such as base stations and mobile switching centers.